武志斌

摘要 为探讨一氧化氮和镁对NaCl胁迫下棉花幼苗生长的影响，以鲁21为试验材料，以适宜浓度的NaCl模拟盐胁迫条件，用一氧化氮供体SNP（硝普纳）和MgSO4溶液浸种，研究了不同浓度一氧化氮（0.05、0.10、0.20 mmol/L）和镁（20、60、80 mg/L）复配浸种处理对NaCl胁迫条件下棉花幼苗生长的影响，以期筛选出能缓解盐胁迫对棉花幼苗生长产生抑制作用的最佳浓度组合。通过观察种子发芽情况，测定幼苗的SOD活性、POD活性、根系活力、叶绿素含量、脯氨酸、叶片电导率、丙二醛含量等相关指标。结果表明，一氧化氮和镁复配浸种对棉花幼苗的耐盐性有显著影响，可显著提高NaCl胁迫条件下幼苗根系活力、POD活性、叶绿素含量、脯氨酸含量及SOD活性，能显著降低幼苗叶片的电导率及MDA含量，其中0.1 mmol/L的SNP和60 mg/L的MgSO4复配浸种处理对提高盐胁迫下棉花幼苗的生长势效果最好。

关键词 棉花;盐胁迫;一氧化氮;镁;幼苗生长

中图分类号 S562文献标识码 A

文章编号 0517-6611（2021）08-0054-03

doi：10.3969/j.issn.0517-6611.2021.08.014

开放科学（资源服务）标识码（OSID）：

Effects of Nitric Oxide and Magnesium on Cotton Seedling Growth under NaCl Stress

WU Zhi-bin （Xinxiang Soil and Fertilizer Workstation， Xinxiang， Henan 453003）

Abstract In order to explore the effects of nitric oxide and magnesium on the growth of cotton seedlings under NaCl stress， Lu 21 was used as experimental material， and the seeds were soaked with SNP （nitroprusside） and MgSO4 solution with appropriate concentration of NaCl.The effects of different concentrations of SNP（0.05， 0.10， 0.20 mmol/L） and Mg （20， 60， 80 mg/L） were studied， so as to screen out the best concentration combination which can alleviate the inhibition effect of salt stress on the growth of cotton seedlings.By observing the germination of seeds， the SOD activity， POD activity， root activity， chlorophyll， proline， leaf conductivity， malondialdehyde content and other related indicators of the seedlings were determined.The results showed that the combined soaking of nitric oxide and magnesium had a significant effect on the salt tolerance of cotton seedlings.For example， the root activity， POD activity， chlorophyll， proline content and SOD activity of seedlings under salt and NaCl stress could be significantly improved.To reduce the electrical conductivity and MDA content of the leaves of the seedlings， the combination of 0.1 mmol/L SNP and 60 mg/L MgSO4 in combination for seed soaking was the best way to improve the growth vigor of cotton seedlings under salt stress.

Key words Cotton;Salt stress;Nitric oxide;Magnesium;Seedling growth

棉花是較耐盐碱的作物，其耐盐能力因生育阶段而不同。有研究表明，种子萌发和幼苗生长阶段是棉花耐盐能力较弱的时期，因此也是对棉花品种进行耐盐性筛选的关键时期[1-3]。镁是植物叶绿素的重要组成成分之一，植物一旦缺镁，会破坏叶绿体结构，导致基粒数、类囊体数下降[4]。镁是植物体内多种酶的活化剂，盐胁迫下Mg2+吸收量减少，会对植物的生长发育产生极为不利的影响[5]。一氧化氮不仅介导了植物防御相关基因的表达、细胞程序性死亡、脱落酸诱导的气孔关闭 [6]，还参与了种子萌发、胁迫响应、成熟和衰老等生理过程，特别是提高植物抗逆性的作用引起了人们的关注[7-10]。……